LevTrim
Level and Trim

Automatically adjust sound level to equal apparent sound
level
according to the replaygain.org
specification and without clipping,
trim off silence, fade in/out, and encode/decode
one or several mp3 or wav files,
in single or batch mode.
Can be used with a regular Windows graphic interface,
or it can be used on the command line,
or it can be used as a plug-in to Audiograbber.